Abstract: The temperature probe is biased for causing current flowing therethrough to be proportional to the probe temperature. A variable set point temperature is represented by a variable reference current which is summed with the temperature probe current. An output signal is produced therefrom to indicate the relationship between the set point temperature and the probe temperature.

Abstract: A method and means for programming the operation of an apparatus having at least a plurality of different control functions provides a control panel, an arrangement for causing the control panel to appear blank prior to initial activation of the apparatus, circuitry for initially activating the apparatus, and circuitry responsive to initial activation for indicating and allowing selection of the different control functions, the circuitry for indicating and allowing selection including circuitry for sequentially displaying the control functions on the control panel to allow selection thereof.

Abstract: Disclosed is a control system for controlling the operation of an appliance and the like which is particularly adaptable for controlling at least one operation variable of an apparatus for drying articles such as a clothes dryer, washer-dryer or similar type of appliance. The drying apparatus is capable of accurately drying any number of articles to a desired degree of dryness irrespective of time by sensing a plurality of temperatures and deriving a final temperature difference for each load of articles indicative of the degree of dryness desired. Furthermore, the control system provides the ability to optionally control the drying apparatus by timing its operation, to control the temperature of the air used for drying, to reduce the temperature of the air used for drying before the completion of an operation cycle so as to avoid setting wrinkles, and to determine and indicate when excessive lint has accumulated on the lint filter.

Abstract: An inductance element, such as a coil, cooperates with a detector/amplifier circuit to detect the level of a liquid in a container by quenching oscillations in an electrical circuit when the liquid is brought into close proximity to the inductance element.

Abstract: Power is applied to an AC load at the crest of a voltage waveform by employing a light emitting diode. The crest firing circuit further includes a detector responsive to the diode's light emitting properties which fires a semiconductor switching device thereby activating the AC load.

Abstract: A programmable timing device includes a plurality of rotatable discs, three of which are concentrically rotatable about a common axis, one of which is eccentrically rotatable about another axis, and three light sources. Opaque portions of the four discs periodically mask and expose the three light sources whereby detectors activate and deactivate the timing device and activate a machine function in a programmed sequence of two time intervals at two dissimilar power levels. The two power levels are determined by independently moving two of the light sources in horizontal directions whereby one of the four rotating discs periodically exposes each light source for variably controllable time periods during each of the programmed time intervals. The exposure of the horizontally movable light sources is further controlled by the rotation of another one of the four rotating discs by determining which of the light sources is exposed to the detector for actuating the machine function during each time interval.

Abstract: In a refrigeration mechanism including a refrigerant, a means for pressurizing the refrigerant, a means for liquifying the refrigerant, a means for vaporizing the refrigerant, and a means for circulating air to be refrigerated, the improvement comprising a means for sensing frost accumulation which includes a capacitance sensitive element disposed within the means for vaporizing the refrigerant.

Abstract: Electrodes are disposed on portions of a container comprising dielectric material, an electrical signal is capacitively transmitted between said electrodes, said electrical signal is shunted by the presence of a liquid in close proximity to said electrodes, and said shunting is detected.

Abstract: Starting at the same time, two timing means produce a series of output pulses at slightly different frequencies. When the two output pulses coincide, a single output pulse is produced. This will occur at a frequency equal to the difference between frequences of two original timing means and the interval between the single outputs will increase as the difference between the frequencies of the two timing means is made smaller.